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<?php function getSundays($y, $m) { return new DatePeriod( new DateTime("first Sunday of $y-$m"), DateInterval::createFromDateString('next sunday'), new DateTime("last day of $y-$m") ); } $days=""; foreach (getSundays(2016, 04) as $Sunday) { $days[] = $Sunday->format("d"); } var_dump($days);

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